======================================
| [  279.966036][    C1] 1 lock held by swapper/1/0:
| [ 279.966238][ C1] #0: ffffc900001c0d60 ((&icsk->icsk_retransmit_timer)){+.-.}-{0:0}, at: call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1737) 
| [  279.966633][    C1]
| [  279.966633][    C1] stack backtrace:
[  279.966880][    C1] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[  279.966883][    C1] Call Trace:
[  279.966885][    C1]  <IRQ>
[ 279.966888][ C1] dump_stack_lvl (lib/dump_stack.c:123) 
[ 279.966895][ C1] print_usage_bug.part.0 (kernel/locking/lockdep.c:4048) 
[ 279.966899][ C1] mark_lock_irq (kernel/locking/lockdep.c:4013 kernel/locking/lockdep.c:4059 kernel/locking/lockdep.c:4270) 
[ 279.966904][ C1] ? save_trace (kernel/locking/lockdep.c:595) 
[ 279.966912][ C1] mark_lock (kernel/locking/lockdep.c:4756) 
[ 279.966916][ C1] mark_usage (kernel/locking/lockdep.c:4645) 
[ 279.966919][ C1] __lock_acquire (kernel/locking/lockdep.c:5194) 
[ 279.966924][ C1] lock_acquire.part.0 (kernel/locking/lockdep.c:473 kernel/locking/lockdep.c:5873) 
[ 279.966927][ C1] ? xa_set_mark (lib/xarray.c:2076 lib/xarray.c:2146) 
[ 279.966930][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 279.966936][ C1] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 279.966938][ C1] ? xa_set_mark (lib/xarray.c:2076 lib/xarray.c:2146) 
[ 279.966941][ C1] _raw_spin_lock (./include/linux/spinlock_api_smp.h:134 kernel/locking/spinlock.c:154) 
[ 279.966944][ C1] ? xa_set_mark (lib/xarray.c:2076 lib/xarray.c:2146) 
[ 279.966947][ C1] xa_set_mark (lib/xarray.c:2076 lib/xarray.c:2146) 
[ 279.966949][ C1] ? __pfx_xa_set_mark (lib/xarray.c:2144) 
[ 279.966952][ C1] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 279.966957][ C1] ? find_held_lock (kernel/locking/lockdep.c:5353) 
[ 279.966961][ C1] ref_tracker_dir_exit (lib/ref_tracker.c:54 lib/ref_tracker.c:223) 
[ 279.966965][ C1] ? trace_kfree (./include/trace/events/kmem.h:94 (discriminator 21)) 
[ 279.966971][ C1] ? kfree (mm/slub.c:4831) 
[ 279.966974][ C1] ? _raw_spin_unlock_irqrestore (./include/linux/spinlock_api_smp.h:151 kernel/locking/spinlock.c:194) 
[ 279.966978][ C1] ? __pfx_ref_tracker_dir_exit (lib/ref_tracker.c:213) 
[ 279.966982][ C1] ? ref_tracker_free (lib/ref_tracker.c:281) 
[ 279.966985][ C1] ? __lock_acquire (kernel/locking/lockdep.c:5240) 
[ 279.966988][ C1] ? __pfx_ref_tracker_free (lib/ref_tracker.c:281) 
[ 279.966991][ C1] ? __sk_destruct (./include/linux/instrumented.h:96 ./include/linux/atomic/atomic-instrumented.h:400 ./include/linux/refcount.h:389 ./include/linux/refcount.h:432 ./include/linux/refcount.h:450 ./include/net/net_namespace.h:287 ./include/net/net_namespace.h:390 net/core/sock.c:2368) 
[ 279.966997][ C1] ? call_timer_fn (kernel/time/timer.c:1747) 
[ 279.966999][ C1] ? __run_timers (kernel/time/timer.c:1799 kernel/time/timer.c:2372) 
[ 279.967003][ C1] ? run_timer_base (kernel/time/timer.c:2385 kernel/time/timer.c:2376 kernel/time/timer.c:2393) 
[ 279.967006][ C1] __put_net (./include/linux/llist.h:238 ./include/linux/llist.h:265 net/core/net_namespace.c:732) 
[ 279.967013][ C1] ? default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 279.967017][ C1] ? __pfx___put_net (net/core/net_namespace.c:729) 
[ 279.967021][ C1] ? bpf_sk_storage_free (./include/linux/rcupdate.h:341 ./include/linux/rcupdate.h:871 net/core/bpf_sk_storage.c:61) 
[ 279.967027][ C1] __sk_destruct (./include/net/net_namespace.h:288 ./include/net/net_namespace.h:390 net/core/sock.c:2368) 
[ 279.967031][ C1] ? __pfx_tcp_write_timer (net/ipv4/tcp_timer.c:727) 
[ 279.967037][ C1] call_timer_fn (kernel/time/timer.c:1747) 
[ 279.967039][ C1] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1737) 
[ 279.967041][ C1] ? call_timer_fn (./include/linux/lockdep.h:31 kernel/time/timer.c:1737) 
[ 279.967044][ C1] ? __pfx_call_timer_fn (kernel/time/timer.c:1724) 
[ 279.967048][ C1] ? __run_timers (kernel/time/timer.c:1798 kernel/time/timer.c:2372) 
[ 279.967051][ C1] ? __lock_release (kernel/locking/lockdep.c:5539) 
[ 279.967054][ C1] ? rcu_is_watching (./include/linux/context_tracking.h:128 kernel/rcu/tree.c:745) 
[ 279.967058][ C1] __run_timers (kernel/time/timer.c:1799 kernel/time/timer.c:2372) 
[ 279.967061][ C1] ? __pfx_tcp_write_timer (net/ipv4/tcp_timer.c:727) 
[ 279.967067][ C1] ? __pfx___run_timers (kernel/time/timer.c:2343) 
[ 279.967071][ C1] ? do_raw_spin_lock (./arch/x86/include/asm/atomic.h:107 ./include/linux/atomic/atomic-arch-fallback.h:2170 ./include/linux/atomic/atomic-instrumented.h:1302 ./include/asm-generic/qspinlock.h:111 kernel/locking/spinlock_debug.c:116) 
[ 279.967075][ C1] ? __pfx_do_raw_spin_lock (kernel/locking/spinlock_debug.c:114) 
[ 279.967078][ C1] ? lock_acquire (./include/trace/events/lock.h:24 kernel/locking/lockdep.c:5834) 
[ 279.967081][ C1] ? run_timer_base (kernel/time/timer.c:2384 kernel/time/timer.c:2376 kernel/time/timer.c:2393) 
[ 279.967085][ C1] run_timer_base (kernel/time/timer.c:2385 kernel/time/timer.c:2376 kernel/time/timer.c:2393) 
[ 279.967088][ C1] run_timer_softirq (kernel/time/timer.c:2404) 
[ 279.967091][ C1] handle_softirqs (kernel/softirq.c:580) 
[ 279.967096][ C1] __irq_exit_rcu (kernel/softirq.c:614 kernel/softirq.c:453 kernel/softirq.c:680) 
[ 279.967099][ C1] irq_exit_rcu (kernel/softirq.c:698) 
[ 279.967102][ C1] sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1050 arch/x86/kernel/apic/apic.c:1050) 
[  279.967106][    C1]  </IRQ>
[  279.967107][    C1]  <TASK>
[ 279.967109][ C1] asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:702) 
[ 279.967113][ C1] RIP: 0010:pv_native_safe_halt (arch/x86/kernel/paravirt.c:82) 
[ 279.967117][ C1] Code: b4 cc 00 c3 cc cc cc cc 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 66 90 0f 00 2d 53 87 24 00 fb f4 <e9> cc 58 02 00 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
All code
========
   0:	b4 cc                	mov    $0xcc,%ah
   2:	00 c3                	add    %al,%bl
   4:	cc                   	int3
   5:	cc                   	int3
   6:	cc                   	int3
   7:	cc                   	int3
   8:	0f 1f 00             	nopl   (%rax)
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	66 90                	xchg   %ax,%ax
  21:	0f 00 2d 53 87 24 00 	verw   0x248753(%rip)        # 0x24877b
  28:	fb                   	sti
  29:	f4                   	hlt
  2a:*	e9 cc 58 02 00       	jmp    0x258fb		<-- trapping instruction
  2f:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  36:	00 00 00 
  39:	66 90                	xchg   %ax,%ax
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop

Code starting with the faulting instruction
===========================================
   0:	e9 cc 58 02 00       	jmp    0x258d1
   5:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
   c:	00 00 00 
   f:	66 90                	xchg   %ax,%ax
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
[  279.967120][    C1] RSP: 0018:ffffc90000137de8 EFLAGS: 00000242
[  279.967123][    C1] RAX: 0000000000a63a5d RBX: 1ffff92000026fc1 RCX: ffffffffb144c3c9
[  279.967126][    C1] RDX: 0000000000000000 RSI: ffffffffb20bc1ba RDI: ffffffffb185f220
[  279.967127][    C1] RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed1006c16702
[  279.967129][    C1] R10: ffff8880360b3813 R11: ffffffffb2211288 R12: 0000000000000000
[  279.967130][    C1] R13: ffff888001bf8040 R14: dffffc0000000000 R15: 0000000000000000
[ 279.967134][ C1] ? ct_kernel_exit.constprop.0 (kernel/context_tracking.c:146) 
[ 279.967140][ C1] default_idle (./arch/x86/include/asm/paravirt.h:107 arch/x86/kernel/process.c:743) 
[ 279.967142][ C1] default_idle_call (./include/linux/cpuidle.h:143 kernel/sched/idle.c:118) 
[ 279.967144][ C1] cpuidle_idle_call (kernel/sched/idle.c:186) 
[ 279.967148][ C1] ? __pfx_cpuidle_idle_call (kernel/sched/idle.c:168) 
[ 279.967152][ C1] ? tsc_verify_tsc_adjust (arch/x86/kernel/tsc_sync.c:60) 
[ 279.967158][ C1] do_idle (kernel/sched/idle.c:325) 
[ 279.967161][ C1] cpu_startup_entry (kernel/sched/idle.c:422 (discriminator 1)) 
[ 279.967164][ C1] start_secondary (arch/x86/kernel/smpboot.c:203 arch/x86/kernel/smpboot.c:283) 
[ 279.967166][ C1] ? __pfx_start_secondary (arch/x86/kernel/smpboot.c:233) 


Finger prints:
mark_lock_irq:mark_lock:mark_usage:__lock_acquire:_raw_spin_lock